Percarina

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Percarina
Percarina demidoffii.jpg

Percarina ( Percarina demidoffii )

Systematics
Perch relatives (Percomorphaceae)
Order : Perch-like (Perciformes)
Subordination : Percoidei
Family : Real perch (Percidae)
Genre : Percarina
Type : Percarina
Scientific name
Percarina demidoffii
( Nordmann , 1840)

The common percarina ( Percarina demidoffii ) is only in the brackish water occurring bony fish from the family of Real perch (Percidae). The specific epithet honors the magnate and supporter of research into southern Russia Anatole Demidoff . Percarina means small perch, but can also indicate a mediating position of the genus between Perca and Acerina (former name and now subgenus of Gymnocephalus ).

features

The females of this species hardly grow larger than 10 cm, the males stay below. The fish are a bit high back and laterally more compressed than the species of the genus Gymnocephalus . The eyes are large, the distance between the mouth and the eye corresponds to an eye diameter. The large mouth is pointed, the gap in the mouth extends backwards to below the center of the eye. According to Seeley (1886), the grater-like dentition of the lower jaw with several rows of pointed teeth is striking, some of which also protrude outwards - it is reminiscent of those of the snipe eels , which also mainly eat long-legged and multi-legged shrimp (it depends that the "floating shrimp" stick to the lower jaw and not free themselves from the mouth by tearing off individual, easily regenerable extremities with their abdomen recoil). The head sides are bare. The lateral lines of the head are developed similar to those of the ruff (slime pits). The rear edge of the front cover is sawn, the gill cover ends in a wide thorn. The body is covered by small comb scales, 65 to 76 are counted along the sideline . The body is almost translucent. The color of the back is milky white, on both sides of the dorsal fin bases there are usually eight or nine round or irregularly shaped, gray spots. There can also be black dots along the sideline. The spiked rays of the ventral fin are black. The caudal fin is deeply forked.

Fin formula : D1 IX-XII, D2 II-III / 10-13, A II / 8-11; about 33 vertebrae

distribution and habitat

Rivers flowing into the Black Sea

The distribution area of ​​the percarina is in southern Russia , southern Ukraine and probably in the Republic of Moldova . It occurs in the north-western part of the Black Sea and in the estuaries and coastal lakes of the Dniester , Southern Bug and Dnieper . In 1986 it was also found in the Danube Delta ( Romania ). According to Bogutskaja 2008, the species only lives in brackish water with a salinity of 1 to 8 ‰ : it is a relic of the Paratethys . It is most common in water depths of 5 m above black ( eutrophic ) mud.

Way of life

The species lives in schools near the bottom of the water. The main food is benthic invertebrates , but hover shrimp ( Mysida ) and smaller fish (when sexually mature) are also eaten. The animals spawn from May to August in areas close to the coast near the river mouths over sand and muddy bottoms. The spawn, up to 3000 eggs per female, is released into the open water above the bottom, to which it slowly sinks. The development proceeds as with Percarina maeotica .

Existence and endangerment

The percarina is often common in the estuary areas of rivers and in coastal lagoons. Since all large rivers that flow into the Black Sea now have barrages that reduce the inflow of freshwater, the salinity of the species' habitat is increasing, which could threaten it. According to surveys in 1996, the IUCN therefore classified Percarina demidoffii as endangered ( "vulnerable" ).

literature

  • Alexander von Nordmann : Observations sur la fauna pontique. In: Anatole de Démidoff : Voyage dans la Russie méridionale et la Crimée. Vol. III. Voyage Russie Mérid., Paris 1840, pp. 353-635.
  • Harry Govier Seeley : The fresh-water fishes of Europe, a history of their genera, species, structure, habits and distribution. Cassel & Co., London 1886, pp. 31-32.
  • V. Otel, P. Banarescu: First record of Percarina demidofii Nornmann, 1840 from Romania and from the Danube river basin (Pisces, Percidae). In: Revue Roumaine de Biologie. 31, 1, Bucharest 1986, pp. 11-13.
  • YS Reshetnikov, NG Bogutskaya, ED Vasil'eva, EA Dorofeeva, AM Naseka, OA Popova, KA Savvaitova, VG Sideleva, LI Sokolov: An annotated check-list of the freshwater fishes of Russia. In: Journal of Ichthyology. 37, 9, 1997, pp. 687-736.
  • Fritz Terofal: Steinbach's natural guide, freshwater fish. Ulmer, Stuttgart 2003, ISBN 3-8001-4296-1 .

supporting documents

Individual evidence

  1. ^ Nina Bogutskaya: Ecoregion Description 418: Dniester - Lower Danube. Freshwater Ecoregions of the World (FEOW), 2008 (online) ( Memento of the original from March 20, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.feow.org
  2. ↑ Percarina demidoffii in the IUCN Red List of Threatened Species 2010.4. Listed by: World Conservation Monitoring Center, 1996. Retrieved December 10, 2010.

Web links